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101.
A patient with 'spent' polycythaemia vera showed extensive extramedullary haematopoiesis (EMH) in non-haematopoietic tissue clinically resulting in an ischaemic colitis and respiratory symptoms due to lung infiltrates. On laboratory investigation, the EMH also included immature erythroblasts due to acute erythroid leukaemia. It is hypothesised that the abnormal homing of erythroid progenitors might be related to the abnormal expression of antigens, such as CD36. 相似文献
102.
103.
Administered a 4-part questionnaire, including Rotter's Internal-External Control Scale, the Death Anxiety Scale, Belief in Afterlife Scale-Form A, and the Fear of Death Scale, to 300 college-age Ss. Results did not support the hypothesized relationship between belief in an external locus of control and death anxiety or between externality and belief in afterlife. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
The Multiplex Fabry-Perot interferometer (MFPI) consists of a Fabry-Perot interferometer in which the étalon plate separation is changed over a large optical distance. Fourier transformation of the resultant interferogram allows one to treat the multiple reflections within the étalon cavity in a manner analogous to an array of Michelson-type interferometers. However, the scan distance required by the MFPI is much less than for a comparable Michelson. The design and construction of the MFPI are described. Solar absorption spectra measured with this instrument are compared with results from the FASCODE atmospheric model. 相似文献
105.
A compact twelve-channel photon-counting device based on existing Generation II imaging technology has been developed for use as the image-plane detector of the Dynamics Explorer Fabry-Perot interferometer. The device has an S-20 photocathode, three-microchannel plate electron multiplication stages, and an equal-area concentric-ring segmented anode whose geometry mimics that of the interference ring pattern produced by a plane etalon. The twelve channels sample equal and contiguous intervals in the spectrum. The purpose of the development has been to utilize the signal multiplex advantage of a multichannel detector in the measurement of Doppler shifts and line-broadening effects for naturally occurring atmospheric emission features of low intensity. The design, testing, calibration, and flight performance of the novel detector system are presented. In addition, measured emission line profiles at high resolution from the satellite instrument are presented to illustrate the operation of the device. 相似文献
106.
15-Aza-24-methylene-D-homocholesta-8,14-dien-3β-ol, an antimycotic agent, at a concentration of 75 ng/ml inhibited ergosterol
biosynthesis inSaccharomyces cerevisiae strain 3701 B resulting in the accumulation of an unusual sterol. Experimental data presented indicate that this sterol is
ergosta-8,14-dien-3β-ol. The accumulation of the compound is supportive of current models of biosynthetic pathways for sterols
in yeast and is consistent with inhibition by the azasterol of the Δ14 sterol reductase. 相似文献
107.
Jianxiong Xiao Krista A. Ehinger James Hays Antonio Torralba Aude Oliva 《International Journal of Computer Vision》2016,119(1):3-22
Progress in scene understanding requires reasoning about the rich and diverse visual environments that make up our daily experience. To this end, we propose the Scene Understanding database, a nearly exhaustive collection of scenes categorized at the same level of specificity as human discourse. The database contains 908 distinct scene categories and 131,072 images. Given this data with both scene and object labels available, we perform in-depth analysis of co-occurrence statistics and the contextual relationship. To better understand this large scale taxonomy of scene categories, we perform two human experiments: we quantify human scene recognition accuracy, and we measure how typical each image is of its assigned scene category. Next, we perform computational experiments: scene recognition with global image features, indoor versus outdoor classification, and “scene detection,” in which we relax the assumption that one image depicts only one scene category. Finally, we relate human experiments to machine performance and explore the relationship between human and machine recognition errors and the relationship between image “typicality” and machine recognition accuracy. 相似文献
108.
As part of a study on the use of coal-tar pitches as binders in electrode carbons for the aluminium industry, the object of the present work was to attempt to identify textural components in electrode binder cokes. Accordingly, four experimental carbons, made using the same petroleum coke as filler and four coal-tar pitches of differing characteristics as binders, were examined in a scanning electron microscope (SEM) after embedding in resin, polishing and etching in atomic oxygen. Binder cokes could be distinguished from the filler particles and could be characterized in terms of the content of three components, termed lamellar, intermediate and granular. The textural composition of the binder cokes was dependent upon the character of the pitch and the type of quinoline-insoluble components present. Pitch cokes, made by carbonizing the pitches alone, differed markedly from the corresponding binder cokes. The findings are considered in terms of current ideas on pitch carbonization. 相似文献
109.
Schlotter WF Turner JJ Rowen M Heimann P Holmes M Krupin O Messerschmidt M Moeller S Krzywinski J Soufli R Fernández-Perea M Kelez N Lee S Coffee R Hays G Beye M Gerken N Sorgenfrei F Hau-Riege S Juha L Chalupsky J Hajkova V Mancuso AP Singer A Yefanov O Vartanyants IA Cadenazzi G Abbey B Nugent KA Sinn H Lüning J Schaffert S Eisebitt S Lee WS Scherz A Nilsson AR Wurth W 《The Review of scientific instruments》2012,83(4):043107
The soft x-ray materials science instrument is the second operational beamline at the linac coherent light source x-ray free electron laser. The instrument operates with a photon energy range of 480-2000 eV and features a grating monochromator as well as bendable refocusing mirrors. A broad range of experimental stations may be installed to study diverse scientific topics such as: ultrafast chemistry, surface science, highly correlated electron systems, matter under extreme conditions, and laboratory astrophysics. Preliminary commissioning results are presented including the first soft x-ray single-shot energy spectrum from a free electron laser. 相似文献
110.
S.A. Wissel K. ByrumJ.D. Cunningham G. DrakeE. Hays D. Horan D. KiedaE. Kovacs S. MagillL. Nodulman S.P. SwordyR. Wagner S.P. Wakely 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,659(1):175-181
We describe a dedicated cosmic-ray telescope that explores a new method for detecting Cherenkov radiation from high-energy primary cosmic rays and the large particle air shower they induce upon entering the atmosphere. Using a camera comprising 16 multi-anode photomultiplier tubes for a total of 256 pixels, the Track Imaging Cherenkov Experiment (TrICE) resolves substructures in particle air showers with 0.086° resolution. Cherenkov radiation is imaged using a novel two-part optical system in which a Fresnel lens provides a wide-field optical trigger and a mirror system collects delayed light with four times the magnification. TrICE records well-resolved cosmic-ray air showers at rates ranging between 0.01 Hz and 0.1 Hz. 相似文献